Future phones will be stretched to limit

Fancy a smartphone with a screen that can double in size and stretch like rubber?

Or a curtain that acts like a light, illuminating your kitchen, while wallpaper does the same in the adjoining sitting room?

Such devices are one step nearer to reality with the recent development by the University of California of an elastic and transparent organic light-emitting device, or OLED.

The breakthrough comes as smartphone makers Samsung launched the first curved screen phone, with rival LG set to follow soon.

The beauty of the OLED offering from the university is that it can be repeatedly stretched, folded, and twisted at room temperature while still remaining lit and retaining its original shape. The researchers say they “stretched and restretched the OLED 1,000 times, extending it 30% beyond its original shape and size, and it still continued to work at a high efficiency”.

In fact, they discovered it could be stretched to more than twice its original size as it functioned, while it can also be folded 180º and twisted in multiple directions.

“Our new material is the building block for fully stretchable electronics for consumer devices,” said Qibing Pei, a professor at the university and principal investigator on the research.

“We believe that fully stretchable interactive OLED displays that are as thin as wallpaper will be achieved in the near future, and this will give creative electronics designers new dimensions to exploit.”

The material features electrodes made of a network of silver nanowires inlaid in a rubbery polymer. Crucially, the manufacturing process is relatively simple.

Pei, however, tempered his optimism by saying obstacles remained to be overcome.

“There are still major technical challenges,” Pei said. “This includes how to seal these materials that are otherwise sensitive to air. Researchers around the world are racing the clock, tackling the obstacles. We are confident that we will get there and introduce a number of cool products along the way.”

Samsung has stretched the parameters of flexible technology a little with its new curved-from-side-to-side phone, the Galaxy Round, though there are currently no plans for distribution outside of South Korea.

Rival LG is on the verge of launching a top-to-bottom curved phone, reputedly called the G Flex.

Both companies are heavily involved in developing OLED televisions — LG in April unveiled a curved-screen device measuring 55in, priced at a cool $10,000 (€7,400).

However, Samsung and LG are also the subject of investigations into alleged theft of OLED technology from each other — with police searching the Samsung offices in April, while last year, six employees of LG Display were charged over theft of OLED technology from Samsung.
However, in recent months, it was reported that the firms had agreed to drop lawsuits and even go so far as to co-operate.